Thank you for your suggestion. I fixed that error. Now the application can open its home page, but failed to read css/style.css file.
That is when user open its first page here:
http://122.106.189.123:8080/DeliveriesManager-web/ then click the button "Add Delivery", it opens "addDeliveries.jsp" in a new window. Noticed that the page is without css which is supposed to be styled by style.css.
The style.css link is failed to read as well: